I propose that a Real Estate itemtype contain the following properties:
BrokerName: The owner, or the broker representing the owners of the
property.
BrokerOrganization: The name of the Broker or Agent's company.
BrokerTelephone: The telephone number of the broker.
BrokerURL: The URL of the Broker or Brokerage Companies Web site.
PropertyType: The type of property (Single Family Home, Multi-family
Home, Rental)
Price: The offer price or rent of the property.
PriceTerm: The payment cycle that this property's price represents
(Total for homes, Monthly for rentals?)
PriceCurrency: The currency of the price.
Bedrooms: The number of bedrooms.
Bathrooms: The number of bathrooms.
Floors: The total number of levels of the property.
Amentities: A list of a property's features (in format of ItemList).
YearBuilt: The year the propety was built.
LivingArea: The total area of the living space.
LivingAreaUnit: The unit of measurement used to define the living area
(Square Feet, Square Meters).
LotArea: The total area of the property's land.
LotAreaUnit: The unit of measurement used to define the lot's area
(Acres, Square Meters, Hectares).
Properties from Thing
Description: A short description of the item.
Image: URL of an image of the item.
Name: The name of the item.
URL: URL of the item.
Properties from Place
Address: Physical address of the item.
Fax Number: The fax number.
Geo: the geo coordinates of the place.
Maps: a URL to a map of the place.
Photos: Photographs of this place.
Reviews: Review of the item.
Telephone: The telephone number.
I welcome and invite discussion on how this proposal may be improved.
Let's think this through, and try not to complicate it too much.